The invention relates to a vertical Venetian blind according to the preamble of claim 1.
Such vertical Venetian blinds consist of vertical lamellae, held in a support rail and travelling in the support rail longitudinal direction by means of an operating cord and swivellable about their vertical longitudinal axes by means of an operating chain for opening and closing, which constitute, when closed, a curtain-type Venetian blind, these vertical lamellae being made of strip shaped cut-out pieces made of a weft, cloth or foil, the vertical lamellae being connected with each other at their lower free ends with connecting cords, chains or bead chains held on their outer marginal edges so that, when closed, the vertical lamellae constitute a curtain-type Venetian blind, whereas light can penetrate through the Venetian blind, when in the completely or partially opened state which is obtained by twisting of the vertical lamellae about their vertical axes. With the known vertical Venetian blinds, it is however not possible to create separate light transmitting sections and sections which are not light transmitting, since all vertical lamellae together can only be closed or opened so that, when closed, no light can penetrate through. Even in the only completely or partially opened state, light always penetrates through the Venetian blind surface. However, often no light incidence is desired in certain Venetian blind areas, particularly when light is felt as being disturbing for working, for example at the computer.
Therefore, the aim of this invention is to create a vertical Venetian blind according to the type described in the introduction for which simultaneously light transmitting areas and areas which are not light transmitting can be constituted, whereby a complete opening and closing of the Venetian blind is also possible so that the person which is in a room, for example, in an office with computers with a window equipped with a vertical Venetian blind can adjust and regulate by itself the respectively necessary light condiitions.
This aim is achieved for a vertical Venetian blind of the type according to the kind by the characteristics indicated in claim 1.
Accordingly, the vertical Venetian blind according to the invention is configured in such a way that a section with manually adjustable vertical lamellae is constituted in the lower Venetian blind area in the Venetian blind formed by the vertical lamellae.
The invention further relates to at least one vertical lamella of the vertical lamellae constituting the Venetian blind which is constituted by two parts and which shows an upper lamella section and a lower lamella section which can be twisted about its vertical axis to the upper lamella section in angular positions up to at least 90xc2x0 to the upper lamella section by means of a lockable rotary holding device so that the lower lamella section can be transferred into an angular position of 90xc2x0 to the upper lamella section.
With such a configuration according to the invention of a vertical Venetian blind, it is possible, depending on the arrangement and number of the vertical lamellae constituted by two parts, to obtain a Venetian blind with which different light conditions can be created so that, for example, a person working at a computer can darken the area of the Venetian blind which causes, when opened, a disturbing light incidence, whereas other sections or areas of the Venetian blind can be opened for an incidence of light. Thus, it is possible to adjust the light conditions quite individually and to adapt them to the respective requirements.
Further advantageous configurations of the invention are the object of the subclaims.
According to an advantageous embodiment of the invention, at least one vertical lamella of the vertical lamellae constituting the Venetian blind consists of at least two superimposed lamella sections complementing to the whole length of the vertical lamellae, whereby both lamella sections are connected with each other over the rotary holding device which consists of two retaining clamps twistable about a common vertical middle axis, placed superimposed, the upper retaining clamp being fixed to the lower free end of the respectively upper lamella section and the lower retaining clamp being held at the upper end of the respectively lower lamella section of the vertical lamella. The swivelling range or rotating range of both retaining clamps to each other is limited by means of a locking device, whereby the upper lamella sections and the remaining vertical lamellae are travelling by means of the operating cord and/or the operating chain and/or are swivellable about their vertical axes and the lower lamella sections are manually swivellable and/or swivellable over the upper lamella sections about their vertical rotation axes.
All vertical lamellae which constitute the Venetian blind consist of respectively two lamella sections connected over the rotary holding devices, whereby both lamella sections of each vertical lamella can have the same length or a different length.
Each rotary holding device which respectively connects two lamella sections consists of two superimposed arranged retaining clamps configured as flat bars with approximately rectangular or square recesses configured at the end thereof with openings changing into the respectively upper longitudinal edges of the flat bars, whereby both flat bars have in the middle of their longitudinal edges turned to each other respectively one circular or partially circular disk body, the disk body on the upper retaining clamp being provided with a journal and the disk body on the lower retaining clamp having a bore hole for receiving the journal for constituting the rotation axis. The locking device consists of a curved, particularly of a curved oblong hole in the shape of a quarter of a circle or of a groove in the disk body of the lower retaining clamp of the rotary holding device and of a cam engaging into the oblong hole on the lower side of the disk body of the upper retaining clamp of the rotary holding device so that in parallel position of both retaining clamps the cam of the upper retaining clamp rests in the one end area of the oblong hole and in right-angled position of both retaining clamps to each other the journal rests in the other end area of the oblong hole.
The rotary holding device with its retaining clamps consists of plastic, the flat bars of the retaining clamps of the rotary holding device having a length which is bigger than the width of the individual vertical lamellae so that the free ends with the recesses of the flat bars project laterally from the lamella sections.
The partially circular oblong hole on the disk body of the lower retaining clamp of the rotary holding device approximately corresponds to the length of a quarter of a circle.
The lower lamella sections of the vertical lamellae are connected with each other on both sides in the area of their lower free ends over connecting chains, bead chains or connecting cords, the upper lamella sections of the vertical lamellae being connected with each other on both sides in the area of their lower ends over connecting chains, bead chains or connecting cords.